SQL Server

Get a Header Attribute of a Related Item

Demonstrates the Chilkat Email.GetRelatedAttr method, which returns a header-field attribute value from a header field of the Nth related item. The first argument is the zero-based related-item index, the second names a header field, and the third names an attribute within it. This example loads an image from a file into a BinData object, adds it as a related item with AddRelatedBd (capturing the generated Content-ID and referencing it from the HTML), then reads the name attribute of the related item's Content-Type header.

Background: Related items (inline images, style sheets) are MIME parts whose headers may carry named parameters — for instance Content-Type: image/png; name="logo.png". Because an image is binary, it is loaded into a BinData object (here from a file) and added with AddRelatedBd, rather than being treated as text. GetRelatedAttr then extracts one named attribute from a chosen header of a specific related part, the related-item analogue of GetAttachmentAttr, so you don't have to parse the raw header yourself.

Chilkat SQL Server Downloads

Download Chilkat for SQL Server

SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    --  Demonstrates the GetRelatedAttr method, which returns a header-field attribute value
    --  from a header field of the Nth related item.  The first argument is the zero-based related-item
    --  index, the second is the header field name, and the third is the attribute name.

    DECLARE @email int
    EXEC @hr = sp_OACreate 'Chilkat.Email', @email OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    EXEC sp_OASetProperty @email, 'Subject', 'GetRelatedAttr example'

    --  Load the image data from a file into a BinData object.
    DECLARE @bdImage int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @bdImage OUT

    EXEC sp_OAMethod @bdImage, 'LoadFile', @success OUT, 'qa_data/images/logo.png'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @bdImage, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @email
        EXEC @hr = sp_OADestroy @bdImage
        RETURN
      END

    --  Add the image as a related item from the BinData; capture its generated Content-ID.
    DECLARE @cid nvarchar(4000)
    EXEC sp_OAMethod @email, 'AddRelatedBd', @cid OUT, 'logo.png', @bdImage
    EXEC sp_OAGetProperty @email, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @email, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @email
        EXEC @hr = sp_OADestroy @bdImage
        RETURN
      END

    --  Reference the related item in the HTML body by its Content-ID.
    DECLARE @sbHtml int
    EXEC @hr = sp_OACreate 'Chilkat.StringBuilder', @sbHtml OUT

    EXEC sp_OAMethod @sbHtml, 'Append', @success OUT, '<html><body><img src="cid:PLACEHOLDER_CID"/></body></html>'
    DECLARE @numReplaced int
    EXEC sp_OAMethod @sbHtml, 'Replace', @numReplaced OUT, 'PLACEHOLDER_CID', @cid
    EXEC sp_OAMethod @sbHtml, 'GetAsString', @sTmp0 OUT
    EXEC sp_OAMethod @email, 'SetHtmlBody', NULL, @sTmp0

    --  Get the "name" attribute of the related item's Content-Type header (index 0).
    DECLARE @val nvarchar(4000)
    EXEC sp_OAMethod @email, 'GetRelatedAttr', @val OUT, 0, 'Content-Type', 'name'

    PRINT 'Related item Content-Type name attribute: ' + @val

    --  Note: The path "qa_data/images/logo.png" is a relative local filesystem path,
    --  relative to the current working directory of the running application.

    EXEC @hr = sp_OADestroy @email
    EXEC @hr = sp_OADestroy @bdImage
    EXEC @hr = sp_OADestroy @sbHtml


END
GO